Reverse flow by-pass valve



Feb. 16, 1954 F. 1 MILLER REVERSE FLOW BYPASS VALVE 2 sheets-smet 1 Filed Apri'l T, 1952 za-Z Fig. 5

' F. L. MILLER REVERSE FLOW BY-PASS VALVE Feb. 16, 1954 2 Sheets-Sheet 2 Filed April 7, 1952 Le 4L oooOoo `gooi;

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l sa as zy Patented Feb. 16, 1954 REVERSE FLOW Blf-.PASS VALVE Frank L. Miller, Zi'onsville, Ind., assignor'to. Shell Development4 Company,` Emeryville, Galli., a.

corporation of Delaware Application April 7, 1952.S'rial INo. 280,865

4 Claims. (Cl. 137-87) This invention relates to an automatic reverse flow system for the transportation of' liquids, and pertains more particularly to a reverse flow hypass'valve structure used in said system, which is an improvement on the valve disclosed in U. S. Letters Patent 2,456,566 to Plank.

The system of the present invention is espe cially applicable to pipe line systems connecting a storage or terminal tank to a main pipe line Where the liquid is transported between the pipe line and said tank by a single delivery line having attached to it, for the purpose ofl transporting liquid from the storage'tank to main pipe line, a pump which must be by-passed when liquid is delivered from main pipe line to storage tank.

For this purpose, the pump in communication with the tank is usually by-passed by means ofa byf-pass line and a suitable valve arrangement to protect' said pump, since certain types of pumps are damaged when run backwards bythe force' of the liquid being delivered. Other pumps are bypassed because they cannot be run backwards and thus prevent the liquid from entering the tank.

The above-mentioned pump foy-pass liney may have installed in it any desired type of manually operated or remote control. valve, Since remote control valves and their means of operation often necessitate a considerable amount of inspection and maintenance, and since the use of manually "operated valves is costly in requiring the use of operators, it is desirable to provide a flow system Avalve 0r plus member whose action substantially eliminates or minimizes hammering.

Other objects of this invention will appear from the following description taken with reference to the attached drawings, wherein;

Figures 1 and 2 are schematic diagrams of asystem employing the present valve in eacyn of its twol Operating positions,

,Figures 3 and Al are longitudinal orossseetional views showinstheoonstruotion .ortho reverse--1flw byapass valve;

.2.8, as shown at and 36.

abats a; lianes 42 *which Referring to- Figures i and '2 of the drawing, a system in which the present reverse flow by-pass valve structure II is employed may comprise a main pipe line I2, a pump I3 and a tank I4. The pipe line I2 is connected to the pump i3 and the tank I4y by-means ofv a conduit or single delivery line I5, the present automatic valve II, a pump by-pass lineV IG, and a branch line I1, which may be provided with ay valve I8.

The reverse owlay-pass valve structure, as illustrated in Figures 3 and 4, comprises a cylindrical valve housing 2| having flanges 22 and 23 formed on or aiiixed in any suitable manner to oppositeA ends thereof. A Il uidport 24 which is out through the wall of said housingr 2l is surrounded by a short pipe section 25 which may be welded to the housing, thus forming a T with the housingl 2|. A ange 25 is provided on this pipe section 25 for attachingthe valve Astructure to by-pass line Iii (Figure 1). v'lhe flanges 22 and 23; at opposite' ends of the valve structure, are-connected to lines II and I5, respectively.

A pair of internallanges or annular rings 2l and 2 il (Figures 3 and 4) are secured in any suitable iluidtight manner tothe inner wall of the housing 2|. For example, one internal ange 2l may be flxedly welded, as at 30, to the housing 'ZI While the othervinternal ilange 2 8 may be removably attached to the housing- 2I by a plurality of screws or bolts'l threaded through the housing 2| into tapped holes 32 in the ilange 28. Preferably, atleast one o f the internal flanges 2'! and 2 8 is secured within the valve housing 2| in a removable manner for easy disassembly of the valve for maintenance purposes. The removable 'flange 28' may be provided with a recessed O-ring seal 33 for forming a fluidtight seal with the innerwall of the housing 2I.

Disposed concentri'cally within the valve housng2-I between the internal anges 2'! and 23 is a liner or sleeve Si whose ends may be recessed in grooves out in adjacent' faces of the 'flanges 2l and Mounted for sliding movementwithin the sleeve 3a between flanges 2'! and-L28 isa piston'v 31 vhaving both ends open with an; internal' flange 38A Iormed at one open end. Slidably mounted within the piston 3l and extendable through the hanged end 38 thereof vis a secondary or pilot piston. provided with external anges 4I and 4-2 which act as stops when they contact opposite sides of iiange 38 on piston 3 'I, thus limitingthe movement of the secondary piston 419g kTheenlelosure' 43 ofthe secondary Piston '4t er 'b formed ofi-olie or' more disesM-fan'd '4'5-hav1n'g'a'- diameter larger than the piston 40, said discs being bolted to said piston by bolt 46 and nut 41. Preferably, the seating disc 44 is made of a plastic or nonmetallic material which can seat against the flange 38 in a iluidtight manner. The cylindrical Wall of the secondary piston is provided with a plurality of ports 48 over the major portion thereof to permit the passage of fluid therethrough when the secondary piston is in its extended position as shown in Figure 4. The secondary piston 40 is preferably not longer than piston 31 and has a length such that the seating disc 44 contacts ange 38 of a piston 31 in its fully retracted position. For illustration purposes the piston 40 is shown in its partially retracted position in Figure 3. The diameter of the secondary piston 4U is of a size to form a substantially'fluidtight fit with the flange 38 of piston 31.

'I'he liner or sleeve 34 is preferably arranged in concentric spaced relationship with the bore of the valve housing whereby an annular fluid passageway 50 is formed between the sleeves 34 and the inner wall of the housing 2|. It is'realized, however, that the present valve can operate, al-

though With a smaller flow therethrough, if the sleeve 34 is not spaced from the housing 2| -to form annular space 50, but on the other hand fits snugly within the bore of the housing 2|. The sleeve 34 is approximately about twice the length of the piston 31 or the diameter of side port 24. The portion of the sleeve 34 adjacent the port 24 is provided with a plurality of holes 5| which preferably extend in circumferential rows entirely around the sleeve, as shown in Figure 3, whereby fluid entering the sleeve 34 can rapidly pass through the perforations I into the annular fluid passageway 50 and out the port 24.

The piston 31 which is slidably mounted in the sleeve 34 is of a length sufficient to close all perforations 5| in said sleeve when the piston is at one limit of its travel and open the perforations 5I when it is at its other limit of travel. Preferably, the piston 31 is provided near either end thereof with circumferential grooves, 52 and 53 in the outer surface thereof for receiving sealing rings 54' and 55 which form a more positive fluidtight seal between the piston 31 and the inner wall of the sleeve 34.

In operation, the present reverse flow by-pass valve is installed in the discharge line I5 from 4the pump I3, as illustrated in Figures 1 and 2, with the pistons 31 and 4|) tending to move away from the pump to allow the flow of fluid to pass axially through the valve housing 2|. Assuming the pistons 31 and 40 to be in the position shown in Figure 3 when the pump is started, fluid enters housing 2| from the left, flows past ange 28, and enters the open end of the secondary piston 40. The uid flow pushes the secondary piston 40 forwardI (to the right, as viewed) until external flange 4| on said piston 40 contacts the flange 38 on the main piston 31. Both pistons 31 and 40 then move forward together until the main piston 31 is stopped by the internal flange 21 secured to the housing 2|, as illustrated With the pistons 31 and 40 in the positions shown flange 21, the ports 5I in sleeve 34 are effectively sealed so that the flow of fluid continues through the ports 48 in the extended secondary piston 40 and out of the housing 2| into pipe line I5 (Figure 2).

When the flow through pipe line I5 is reversed and it is desired to deliver fluid from the main vvpipe line I2 to the storage tank |4 Without going ythrough the pump I3, ythe present reverse ow by-pass valve operates in the following manner. With the pistons 31 and 40 in the positions shown in Figure 4, a flowing fluid stream entering the housing at the right (as viewed) and flowing to the left, subjects the closed end 43 of the secondary piston 40 to sufficient pressure to force the piston 40 to the left Within the main piston 31 until the seating plate 414 of the secondary piston 40 seats against the flange 38 of the main piston 31 effectively closing perforations 43 in the piston 40.

Both pistons 31 and 40 are then forced to the left under the pressure of the flow stream until they are stopped from further movement by the internal flange 28 as illustrated in Figure 3. At this time the perforations 5| in the sleeve are open allowing fluid entering the housing 2| from pipe line I5 to pass through said perforations 5I, out port 24, into by-pass line and thence through line I1 and valve I8 into the storage tank I4.

In some pumping installations the relative position and height of the storage tank I4 and main pipe line |2 permit deliveries of fluid to be made by gravity from the storage tank when it is substantially full. Assuming that the pistons 31 and 40 are in the positions shown in Figure 3, fluid being delivered from storage tank I4 flows past valve |8 (Figure 1) through lines l1 and I6 and into the side port 24 of the valve Since perforations 5| (Figure 3) are open, the iiuid flows therethrough and out of the valve housing 2|, into line I5 which connects with the main pipe line I2. Flow of fluid will continue in the .above-described manner until the pressure in the line drops below the normal pressure requirements for delivery of fluid from the tank I4 (Figure l) to pipe line I2. At this time, to complete the delivery, it is only necessary to start the pump |3. The pistons 31 and 43 are then pushed out to cover perforations 5| as shown in Figure 4 causing the pressure of duid entering the valve housing 2| to equal the rated pressure of the pump, thus permitting the same amount of fluid to pass on to the pipe line I2 without manual assistance to attain the desired pressure for the remainder of the delivery.

It may be seen that the present reverse flow by-pass valve provides a 2-way valve structure of simple and sturdy design adapted to be opened in one direction at a time by the flow of fluid passing therethrough, the setting of the valve depending upon the direction in which the fluid enters the valve housing. The present valve operates efficiently and quietly at all times without chattering or causing hammering in the pump discharge line as is the case with many control valves. While the present valve has been illustrated as mounted for operation in a horizontal position, its design and construction permit mountingv so that the piston travel is either in a horizontal or vertical plane, or at any desired angle thereto.

I claim as my invention:

1. A reverse flow by-pass valve for pipe lines comprising an elongated tubular housing having open ends for connection into a pipe line, radial port means through the wall of ,said housing intermediate the ends thereof for connection to a pipeline, first and second internal abutments aihxed to the inner Wall of said housing on opposite sides of said port means, a tubular sleeve mounted between said abutments, first aperture means through a portion of said sleeve adjacent lsaid port means, a tubular main piston mounted for limited sliding movement within ,said sleeve between said abutments, said piston being open at both ends, internal abutment means formed at one end of said piston, a perforate tubular secondary piston telescopically mounted Within said main piston and having a closed end extensible through the abutment means of said main piston, and external abutments at either end of said secondary piston adapted to engage the internal abutment means of said main piston.

2. A reverse ow by-pass valve for pipe lines comprising an elongated tubular housing having open ends for connection into a pipe line, radial port means through the wall of said housing intermediate theends thereof for connection to a pipeline, rst and second internal abutments aiixed to the inner wall of said housing on opposite sides of said port means, a tubular main piston mounted for limited sliding movement within said abutments, said piston being open at both ends, internal abutment means formed at one end of said piston, a perforate tubular secondary piston telescopically mounted within said main piston and having a closed end extensible through the abutment means of said main piston, and external abutments at either end of l said secondary piston adapted to engage the internal abutment means of said main piston.

3. A reverse ow by-pass valve for pipe lines comprising an elongated tubular housing having open ends for connection into a pipe line, radial port means through the wall of said housing intermediate the ends thereof, said port means being connectable to a by-pass pipe line, rst and second flanges afxed to the inner wall of said housing on opposite sides of said port means, a tubular sleeve mounted between said flanges coaxially Within said housing, rst annularly dispersed aperture means through a portion of said sleeve adjacent said port means, a tubular main piston mounted for limited sliding movement within said sleeve between said flanges for opening and closing said nrst aperture means, said piston being open at both ends, an internal flange formed at one end of said piston, a tubular secondary piston slidably mounted within said main piston and having an open and a closed end extensible through the flanged end of the main piston, external flanges at either end of said secondary piston of a diameter to engage opposite sides of the internal flange of said main piston, and second annularly disposed aperture means through the wall of said secondary piston.

4. A reverse iiow by-pass valve for pipe lines comprising an elongated tubular housing having open ends for connection into a pipe line, radial port means through the Wall of said housing intermediate the ends thereof, said port means being connectable to a by-pass pipe line, first and second annular flanges afxed to the inner wall of said valve housing on opposite sides of said port means, a tubular sleeve mounted between said langes in concentric spaced relationship with said valve housing, rst annularly disposed aperture means through a portion of said sleeve adjacent said port means, a tubular main piston mounted for limited sliding movement within said sleeve between said anges for opening and closing said rst aperture means, said piston being open at both ends, an internal flange formed at one end of said piston, a tubular secondary piston slidably mounted within said main piston and having an open end and a closed end extensible through the flanged end of said main piston, external flanges at either end of said secondary piston o a diameter to engage the internal flange of said main piston, and second annularly disposed aperture means through the wall of said secondary piston, said apertures being closed to fiuid flow when the secondary piston is in its retracted position.

FRANK L. MILLER.

1teferences Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,697,352 Ferris Jan. 1, 1929 2,456,566 Plank Dec. 14, 1948 2,610,859 Wilcox Sept. 16, 1952 

